Earth Overshoot Day

The Ecological Footprint Challenge

Last year, I took a test. You might not think this is the best way to start a blog, but stay with me. The test I took is different. My students and I, during the One Health course I was co-teaching at Washington University in St. Louis, did a group activity and took a test. It was even “fun!” This test is one that everyone, including you, should take and that allows you to calculate your ecological footprint.

An Ecological What?

First, you may ask, “What is an ecological footprint?”  One definition for an ecological footprint is that it is a measure of the ecological assets (all those living species and non-living things that share the planet with us!) a given person or population requires if she/he/they are to continue living the same way as they are right now.

Earth Overshoot Day

In 2018, the estimated ecological footprint, based on the 7.6 billion humans alive that year, was 1.7 “Earths.” This resulted in Earth Overshoot Day 2018 to be on August 1st. In other words, by August 1, 2018, we humans used up the natural resources that were available to us, without damaging the planet or overdrawing on resources, when there were still 152 days remaining in the year. We overshot our resources. We borrowed 152 days from the next year. In fact, Earth Overshoot Day shows that humans use more from nature than could ever be replaced. In 1987, the first recorded Earth Overshoot Day was calculated to be December 19th. In other words, that year we had 12 days of 1987, from December 19th – 31st, when we were in overdraw of the Earth’s resources. The Earth simply could not keep up with the resources we were extracting. Since that first year of recording the timing of Earth Overshoot Day, the date keeps moving farther from December 31st. In 1987, it was calculated on December 19th, but in 2018 it was August 1st. By 2030, projections place Earth Overshoot Day on June 28th if we continue with “business as usual.” Not only is this not sustainable, it is also crazy!

However, as you may have guessed, not all of us are equal in the size of our ecological footprint. Calculations suggest that certain populations use far more than their share of the resources. That’s right you (probably) and me (for sure) use more than our share of Earth’s resources if we want to continue to have a planet habitable for humans and other living beings.  

What’s your Ecological Footprint?

Okay, back to you. Have you ever thought about your individual ecological footprint? When my class and I did it as a group, we came up with 6.2 Earths. When I did mine solo, I came out with 4.2 Earths. If everyone lived like me, we would need 4.2 Earths. I could not believe it. I live in a single car (Prius) family, I walk to work most days, I eat very little animal-based protein, and I gave up plastic straws long ago. It takes 4.2 Earths to keep me going. I wandered how many Earths it must take for just one Kardashian?

The beauty of calculating your own Earth Overshoot Day is that it can wake you up to the planetary cost of letting you … be you. Questions factored into the calculations include, but are not limited to: 1) How often do you eat animal based products? 2) How much of the food you eat is unprocessed, unpackaged or locally grown? 3) What is the size of your house? 4) Do you have electricity in your house? 4) How far td you travel each week by motorcycle or car? 5) How many hours do you fly each year? (This last one is the one that got me!)

I dare each of you to take this test.  If you have 5 to 15 minutes right now, the energy to think about your ecological footprint, and the desire to learn how to decrease this footprint, settle in and click on the link at

This one simply tool allows each of us to consider our ecological footprint and how we might decrease our individual footprint, from the easy to do things such as carpooling, non-fossil fuel based travel like bikes and legs, to recycling.  Then maybe it will stimulate each of us to see how we might help with the more challenging, but imperative, efforts for Planetary Health. We need to come up with the next technological advances in re-useable energies and sustainable food sources and environmental restoration mechanisms.   

Did you do it? Did you take the test? How many planets would we need if everybody lived like you? When is your personal Earth Overshoot Day? Mine was March 28th! Since I took the test, I have been working on ways to move my Earth Overshoot Day away from January 1st and closer to December 31st.    

Take the test! I guarantee it will have you thinking differently and more importantly, I hope acting differently.